Teething tube



FIG. 1 is a front, left side perspective view of a teething tube, showing my new design;

FIG. 2 is a rear, right side perspective view thereof;

FIG. 3 is a left side elevation view thereof;

FIG. 4 is a right side elevation view thereof; and,

FIG. 5 is a front elevation view thereof, the rear elevation view being a mirror image thereof.

The broken lines in the drawings depict portions of the teething tube that form no part of the claimed design. 

CLAIM I claim the ornamental design for a teething tube, as shown and described. 